Input: add Qualcomm PM8941 power key driver

Signed-off-by: Courtney Cavin <courtney.cavin@sonymobile.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Tested-by: Ivan T. Ivanov <iivanov@mm-sol.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

3 files changed, 306 insertions, 0 deletions

diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index ef542f7ad944..4436ab1b9735 100644
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -115,6 +115,18 @@ config INPUT_PCSPKR
           To compile this driver as a module, choose M here: the
           module will be called pcspkr.
 
+config INPUT_PM8941_PWRKEY
+        tristate "Qualcomm PM8941 power key support"
+        depends on MFD_SPMI_PMIC
+        help
+          Say Y here if you want support for the power key usually found
+          on boards using a Qualcomm PM8941 compatible PMIC.
+
+          If unsure, say Y.
+
+          To compile this driver as a module, choose M here: the module
+          will be called pm8941-pwrkey.
+
 config INPUT_PM8XXX_VIBRATOR
         tristate "Qualcomm PM8XXX vibrator support"
         depends on MFD_PM8XXX
diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
index 75b58841d5a7..78ba4c1b8532 100644
--- a/drivers/input/misc/Makefile
+++ b/drivers/input/misc/Makefile
@@ -50,6 +50,7 @@ obj-$(CONFIG_INPUT_PCAP)		+= pcap_keys.o
 obj-$(CONFIG_INPUT_PCF50633_PMU)        += pcf50633-input.o
 obj-$(CONFIG_INPUT_PCF8574)             += pcf8574_keypad.o
 obj-$(CONFIG_INPUT_PCSPKR)              += pcspkr.o
+obj-$(CONFIG_INPUT_PM8941_PWRKEY)       += pm8941-pwrkey.o
 obj-$(CONFIG_INPUT_PM8XXX_VIBRATOR)     += pm8xxx-vibrator.o
 obj-$(CONFIG_INPUT_PMIC8XXX_PWRKEY)     += pmic8xxx-pwrkey.o
 obj-$(CONFIG_INPUT_POWERMATE)           += powermate.o
diff --git a/drivers/input/misc/pm8941-pwrkey.c b/drivers/input/misc/pm8941-pwrkey.c
new file mode 100644
index 000000000000..867db8a91372
--- /dev/null
+++ b/drivers/input/misc/pm8941-pwrkey.c
@@ -0,0 +1,293 @@
+/*
+ * Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
+ * Copyright (c) 2014, Sony Mobile Communications Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/log2.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/reboot.h>
+#include <linux/regmap.h>
+
+#define PON_REV2                        0x01
+
+#define PON_RT_STS                      0x10
+#define  PON_KPDPWR_N_SET               BIT(0)
+
+#define PON_PS_HOLD_RST_CTL             0x5a
+#define PON_PS_HOLD_RST_CTL2            0x5b
+#define  PON_PS_HOLD_ENABLE             BIT(7)
+#define  PON_PS_HOLD_TYPE_MASK          0x0f
+#define  PON_PS_HOLD_TYPE_SHUTDOWN      4
+#define  PON_PS_HOLD_TYPE_HARD_RESET    7
+
+#define PON_PULL_CTL                    0x70
+#define  PON_KPDPWR_PULL_UP             BIT(1)
+
+#define PON_DBC_CTL                     0x71
+#define  PON_DBC_DELAY_MASK             0x7
+
+
+struct pm8941_pwrkey {
+        struct device *dev;
+        int irq;
+        u32 baseaddr;
+        struct regmap *regmap;
+        struct input_dev *input;
+
+        unsigned int revision;
+        struct notifier_block reboot_notifier;
+};
+
+static int pm8941_reboot_notify(struct notifier_block *nb,
+                                unsigned long code, void *unused)
+{
+        struct pm8941_pwrkey *pwrkey = container_of(nb, struct pm8941_pwrkey,
+                                                    reboot_notifier);
+        unsigned int enable_reg;
+        unsigned int reset_type;
+        int error;
+
+        /* PMICs with revision 0 have the enable bit in same register as ctrl */
+        if (pwrkey->revision == 0)
+                enable_reg = PON_PS_HOLD_RST_CTL;
+        else
+                enable_reg = PON_PS_HOLD_RST_CTL2;
+
+        error = regmap_update_bits(pwrkey->regmap,
+                                   pwrkey->baseaddr + enable_reg,
+                                   PON_PS_HOLD_ENABLE,
+                                   0);
+        if (error)
+                dev_err(pwrkey->dev,
+                        "unable to clear ps hold reset enable: %d\n",
+                        error);
+
+        /*
+         * Updates of PON_PS_HOLD_ENABLE requires 3 sleep cycles between
+         * writes.
+         */
+        usleep_range(100, 1000);
+
+        switch (code) {
+        case SYS_HALT:
+        case SYS_POWER_OFF:
+                reset_type = PON_PS_HOLD_TYPE_SHUTDOWN;
+                break;
+        case SYS_RESTART:
+        default:
+                reset_type = PON_PS_HOLD_TYPE_HARD_RESET;
+                break;
+        };
+
+        error = regmap_update_bits(pwrkey->regmap,
+                                   pwrkey->baseaddr + PON_PS_HOLD_RST_CTL,
+                                   PON_PS_HOLD_TYPE_MASK,
+                                   reset_type);
+        if (error)
+                dev_err(pwrkey->dev, "unable to set ps hold reset type: %d\n",
+                        error);
+
+        error = regmap_update_bits(pwrkey->regmap,
+                                   pwrkey->baseaddr + enable_reg,
+                                   PON_PS_HOLD_ENABLE,
+                                   PON_PS_HOLD_ENABLE);
+        if (error)
+                dev_err(pwrkey->dev, "unable to re-set enable: %d\n", error);
+
+        return NOTIFY_DONE;
+}
+
+static irqreturn_t pm8941_pwrkey_irq(int irq, void *_data)
+{
+        struct pm8941_pwrkey *pwrkey = _data;
+        unsigned int sts;
+        int error;
+
+        error = regmap_read(pwrkey->regmap,
+                            pwrkey->baseaddr + PON_RT_STS, &sts);
+        if (error)
+                return IRQ_HANDLED;
+
+        input_report_key(pwrkey->input, KEY_POWER, !!(sts & PON_KPDPWR_N_SET));
+        input_sync(pwrkey->input);
+
+        return IRQ_HANDLED;
+}
+
+static int __maybe_unused pm8941_pwrkey_suspend(struct device *dev)
+{
+        struct pm8941_pwrkey *pwrkey = dev_get_drvdata(dev);
+
+        if (device_may_wakeup(dev))
+                enable_irq_wake(pwrkey->irq);
+
+        return 0;
+}
+
+static int __maybe_unused pm8941_pwrkey_resume(struct device *dev)
+{
+        struct pm8941_pwrkey *pwrkey = dev_get_drvdata(dev);
+
+        if (device_may_wakeup(dev))
+                disable_irq_wake(pwrkey->irq);
+
+        return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(pm8941_pwr_key_pm_ops,
+                         pm8941_pwrkey_suspend, pm8941_pwrkey_resume);
+
+static int pm8941_pwrkey_probe(struct platform_device *pdev)
+{
+        struct pm8941_pwrkey *pwrkey;
+        bool pull_up;
+        u32 req_delay;
+        int error;
+
+        if (of_property_read_u32(pdev->dev.of_node, "debounce", &req_delay))
+                req_delay = 15625;
+
+        if (req_delay > 2000000 || req_delay == 0) {
+                dev_err(&pdev->dev, "invalid debounce time: %u\n", req_delay);
+                return -EINVAL;
+        }
+
+        pull_up = of_property_read_bool(pdev->dev.of_node, "bias-pull-up");
+
+        pwrkey = devm_kzalloc(&pdev->dev, sizeof(*pwrkey), GFP_KERNEL);
+        if (!pwrkey)
+                return -ENOMEM;
+
+        pwrkey->dev = &pdev->dev;
+
+        pwrkey->regmap = dev_get_regmap(pdev->dev.parent, NULL);
+        if (!pwrkey->regmap) {
+                dev_err(&pdev->dev, "failed to locate regmap\n");
+                return -ENODEV;
+        }
+
+        pwrkey->irq = platform_get_irq(pdev, 0);
+        if (pwrkey->irq < 0) {
+                dev_err(&pdev->dev, "failed to get irq\n");
+                return pwrkey->irq;
+        }
+
+        error = of_property_read_u32(pdev->dev.of_node, "reg",
+                                     &pwrkey->baseaddr);
+        if (error)
+                return error;
+
+        error = regmap_read(pwrkey->regmap, pwrkey->baseaddr + PON_REV2,
+                            &pwrkey->revision);
+        if (error) {
+                dev_err(&pdev->dev, "failed to set debounce: %d\n", error);
+                return error;
+        }
+
+        pwrkey->input = devm_input_allocate_device(&pdev->dev);
+        if (!pwrkey->input) {
+                dev_dbg(&pdev->dev, "unable to allocate input device\n");
+                return -ENOMEM;
+        }
+
+        input_set_capability(pwrkey->input, EV_KEY, KEY_POWER);
+
+        pwrkey->input->name = "pm8941_pwrkey";
+        pwrkey->input->phys = "pm8941_pwrkey/input0";
+
+        req_delay = (req_delay << 6) / USEC_PER_SEC;
+        req_delay = ilog2(req_delay);
+
+        error = regmap_update_bits(pwrkey->regmap,
+                                   pwrkey->baseaddr + PON_DBC_CTL,
+                                   PON_DBC_DELAY_MASK,
+                                   req_delay);
+        if (error) {
+                dev_err(&pdev->dev, "failed to set debounce: %d\n", error);
+                return error;
+        }
+
+        error = regmap_update_bits(pwrkey->regmap,
+                                   pwrkey->baseaddr + PON_PULL_CTL,
+                                   PON_KPDPWR_PULL_UP,
+                                   pull_up ? PON_KPDPWR_PULL_UP : 0);
+        if (error) {
+                dev_err(&pdev->dev, "failed to set pull: %d\n", error);
+                return error;
+        }
+
+        error = devm_request_threaded_irq(&pdev->dev, pwrkey->irq,
+                                          NULL, pm8941_pwrkey_irq,
+                                          IRQF_ONESHOT,
+                                          "pm8941_pwrkey", pwrkey);
+        if (error) {
+                dev_err(&pdev->dev, "failed requesting IRQ: %d\n", error);
+                return error;
+        }
+
+        error = input_register_device(pwrkey->input);
+        if (error) {
+                dev_err(&pdev->dev, "failed to register input device: %d\n",
+                        error);
+                return error;
+        }
+
+        pwrkey->reboot_notifier.notifier_call = pm8941_reboot_notify,
+        error = register_reboot_notifier(&pwrkey->reboot_notifier);
+        if (error) {
+                dev_err(&pdev->dev, "failed to register reboot notifier: %d\n",
+                        error);
+                return error;
+        }
+
+        platform_set_drvdata(pdev, pwrkey);
+        device_init_wakeup(&pdev->dev, 1);
+
+        return 0;
+}
+
+static int pm8941_pwrkey_remove(struct platform_device *pdev)
+{
+        struct pm8941_pwrkey *pwrkey = platform_get_drvdata(pdev);
+
+        device_init_wakeup(&pdev->dev, 0);
+        unregister_reboot_notifier(&pwrkey->reboot_notifier);
+
+        return 0;
+}
+
+static const struct of_device_id pm8941_pwr_key_id_table[] = {
+        { .compatible = "qcom,pm8941-pwrkey" },
+        { }
+};
+MODULE_DEVICE_TABLE(of, pm8941_pwr_key_id_table);
+
+static struct platform_driver pm8941_pwrkey_driver = {
+        .probe = pm8941_pwrkey_probe,
+        .remove = pm8941_pwrkey_remove,
+        .driver = {
+                .name = "pm8941-pwrkey",
+                .pm = &pm8941_pwr_key_pm_ops,
+                .of_match_table = of_match_ptr(pm8941_pwr_key_id_table),
+        },
+};
+module_platform_driver(pm8941_pwrkey_driver);
+
+MODULE_DESCRIPTION("PM8941 Power Key driver");
+MODULE_LICENSE("GPL v2");